FlySpeed Data Export

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Performance options

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Performance options determine technical details of data export that can influence data extraction speed along with the speed of a source server operation.

 

Using Multiple threads

By letting FlySpeed Data Export to use multiple threads, higher transfer rates can be achieved while working at modern multi-core systems.

 

Using Transactions

If this option is checked, all queries are executed in transactions, otherwise each query is executed separately.

 

Transaction Isolation Level

Default

Denotes to use transaction isolation level set by a database server by default.

 

Read Committed

Specifies that shared locks are held while the data is being read to avoid dirty reads, but the data can be changed before the end of the transaction, resulting in nonrepeatable reads or phantom data. This option is the SQL Server default.

 

Read Uncomitted

Implements dirty read, or isolation level 0 locking, which means that no shared locks are issued and no exclusive locks are honored. When this option is set, it is possible to read uncommitted or dirty data; values in the data can be changed and rows can appear or disappear in the data set before the end of the transaction. This option has the same effect as setting NOLOCK on all tables in all SELECT statements in a transaction. This is the least restrictive of the four isolation levels.

 

Repeatable Read

Locks are placed on all data that is used in a query, preventing other users from updating the data, but new phantom rows can be inserted into the data set by another user and are included in later reads in the current transaction. Because concurrency is lower than the default isolation level, use this option only when necessary.

 

Serializable

Places a range lock on the data set, preventing other users from updating or inserting rows into the data set until the transaction is complete. This is the most restrictive of the four isolation levels. Because concurrency is lower, use this option only when necessary. This option has the same effect as setting HOLDLOCK on all tables in all SELECT statements in a transaction.

 

Using Forward-only cursors

Forward-only cursors are the fastest query-based cursors. We recommend you to set this option for the waste majority of database servers.

 

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